Malicious PDF — malware analysis report

Static analysis result for SHA-256 f6d5471534d082eb…

MALICIOUS

PDF

86.1 KB Created: 2021-09-21 06:09:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 9e8d8109460f1b6dc80f93aca38db3d8 SHA-1: 67720804c61ad478274112d002fcaa7e647dbbc0 SHA-256: f6d5471534d082eb3ae28acfd4e01fdee158e4b395117fbcbe169a7b97cd45df
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file identified as malicious by ClamAV and an ML classifier. It contains a large number of embedded URLs, many of which point to compromised WordPress upload directories or other potentially malicious sites. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a link farm structure, suggesting the document's primary purpose is to redirect users to external, potentially harmful content. No scripts were extracted, but the overall structure points to a phishing or redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/161450805a5aec---vasupubo.pdf In PDF document text
    • https://netron.pt/app/webroot/media/files/41745960382.pdfIn PDF document text
    • http://immobilieninvestors.de/userfiles/file/2481100003.pdfIn PDF document text
    • http://ranaghatpchsschool.org/userfiles/file/disobimepelefek.pdfIn PDF document text
    • http://cbestdesign.com/ckfinder/images_store/files/mamegonaxovifar.pdfIn PDF document text
    • http://gurgaontaxi.com/pa/trainstation/uploads/image/file/85648917926.pdfIn PDF document text
    • http://savitaco.com/uploads/images/files/69868200609.pdfIn PDF document text
    • https://vibangnhadat.com/uploads/files/femuzimegokonugu.pdfIn PDF document text
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613b597d9a12e---fefavibumaxotorinaxe.pdfIn PDF document text
    • http://maulich.vn/attachment/files/37250603225.pdfIn PDF document text
    • http://evolution-dev.com/file_media/file_image/file/53929429125.pdfIn PDF document text
    • http://sunnyten.net/userData/board/file/85301250151.pdfIn PDF document text
    • http://fullcolorspandoeken.nl/userfiles/file/99964432442.pdfIn PDF document text
    • http://articolo17.it/siti/usr/foto/files/23129148143.pdfIn PDF document text
    • http://zhouzhuank.com/v15/Upload/file/2021951720318550.pdfIn PDF document text
    • http://abwingsde.com/uploads/files/wososigelakoratesipow.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/bcd913decbb67263bac75c8d738f2601/42148748736.pdfIn PDF document text
    • http://opuspoint.com/ckfinder/userfiles/files/49685147495.pdfIn PDF document text
    • https://lacausedeslivres.com/userfiles/file/78481911373.pdfIn PDF document text
    • http://pietroquatriniarchitetto.eu/userfiles/files/kenalet.pdfIn PDF document text
    • https://thic.net/plugin/ce1/ckfinder/userfiles/files/97937143851.pdfIn PDF document text
    • http://peter-crooks.com/userfiles/file/38997868719.pdfIn PDF document text
    • http://www.pvvc.cz/files/82110442211.pdfIn PDF document text
    • http://lerucherdesanges.fr/userfiles/file/nawaviworanikafetegokutes.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=yoruba+movies+2021PDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e8aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8AA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000100c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100C1 10604 bytes
SHA-256: 3f78994bab70998e431d791ad752e716cd3cfdca6696957557751c661104fbca
font_02_sfnt_off00011915.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11915 19504 bytes
SHA-256: f808f6ebc152a05ec5553b0e96c3ef00f34c281f9c4f4c578de2396e90278965